cairn / ke(ə)rn/ • n. 1. a mound of rough stones built as a memorial or landmark, typically on a hilltop or skyline. ∎ a prehistoric burial mound made of stones.2. (also cairn ter·ri·er) a small terrier of a breed with short legs, a longish body, and a shaggy coat.
So cairngorm precious stone, named from a mountain (Gael. Carngorm ‘blue cairn’) where it is found.